@article{oai:soar-ir.repo.nii.ac.jp:00003775,
 author = {Soya,  Keisuke and Terasawa,  Fumiko and Okumura,  Nobuo},
 issue = {2},
 journal = {THROMBOSIS AND HAEMOSTASIS},
 month = {Feb},
 note = {Fibrin polymerisation is mediated by interactions between knobs 'A' and 'B' exposed by thrombin cleavage, and holes 'a' and 'b'. We demonstrated markedly delayed thrombin-catalysed fibrin polymerisation, through B:b interactions alone, of recombinant gamma D364H-fibrinogen with impaired hole 'a'. To determine whether recombinant variant fibrinogens with no release of fibrinopeptide A (FpA) polymerise similarly to gamma D364H-fibrinoge, we examined two variant fibrinogens with substitutions altering knob 'A', A alpha 17A- and A alpha 17C-fibrinogen. We examined thrombin- or batroxobin-catalysed fibrinopeptide release by HPLC, fibrin clot formation by turbidity and fibrin clot structure by scanning electron microscopy (SEM) and compared the results of the variants with those for gamma D364H-fibrinogen. Thrombin-catalysed FpA release of A alpha 17A-fibrinogen was substantially delayed and none observed for A alpha 17C-fibrinogen; fibrinopeptide B (FpB) release was delayed for all variants. All variant fibrinogens showed substantially impaired thrombin-catalysed polymerisation; for A alpha 17A-fibrinogen it was delayed less, and for A alpha 17C more than for gamma D364H-fibrinogen. No variants polymerised with batroxobin, which exposed only knob 'A'. The inhibition of variant fibrinogens' polymerisation was dose-dependent on the concentration of either GPRP or GHRP, and both peptides that block holes 'b'. SEM showed that the variant clots from A alpha 17A- and gamma D364H-fibrinogen had uniform, ordered fibres, thicker than normal, whereas A alpha 17C-fibrinogen formed less organised clots with shorter, thinner, and tapered ends. These results demonstrate that FpA release per se is necessary for effective B:b interactions during polymerisation of variant fibrinogens with impaired A:a interactions., Article, THROMBOSIS AND HAEMOSTASIS. 109(2):221-228 (2013)},
 pages = {221--228},
 title = {Fibrinopeptide A release is necessary for effective B:b interactions in polymerisation of variant fibrinogens with impaired A:a interactions},
 volume = {109},
 year = {2013}
}